Where is Aunt FLO?!!! Could I be pregnant and it not show on test?

I only log sex “♥️” when we have UNPROTECTED sex. We are NOT ttc anymore because we have 2 babies now, and our youngest is only 1. She is still breastfeeding. I’m freaking just a tad. I’ve taken 6 tests my last test being Wednesday and they were all negative. I stopped testing bc I’m guessing I’m not pregnant.